Self-releasing hopper lock



-- 2 Shets-Sheet l G. KIRK i \qg ,.IN\/ENTORS ROBERT F. SCHMIDT -HENRY A. LEIDECKER DONALD R. F. SCHMIDT ETAL SELF-RELEASING HOPPER LOCK April 11, 1967 Filed June 29. 1964 EVE April 11, 1967 R. F. SCHMIDT ETAL 3,

SELF-RELEASING HOPPER LOCK Filed June 29, 1964 I 2 Sheets-Sheet 2 TNVENTORS ROBERT F. SCHMIDT HENRY A. LEIDECKER DONALD G. KIRK ATTORNEYS United States Patent 3,312,992 SELF-RELEASING HOPPER LOGK Robert F. Schmidt, Elgin, Henry A. Leidecker, Wheaten, and Donald G. Kirk, Elgin, 111., assignors to Elgin Swee er Company, Eigin, Ill., a corporation of Delaware Filed June 29, 1964, Ser. No. 378,641 15 Claims. (Cl. 15-83) The present invention relates generally to a new and improved street sweeper. More particularly, this invention relates to a street sweeper having a self releasing and self locking hopper lock for rigidly securing a dirt hopper to the dump door in a closed position when the street sweeper is picking up sweepings or travelling to and from a dumping station. The self releasing hopper lock may be released when the dirt hopper is moved through an are away from the sweeper permitting the dump door to swing open upon being released so that the contents can be emptied.

An important object of this invention is to provide a new and improved street sweeper having a self releasing, self locking hopper lock thereon.

Still another important object of this invention is to provide a hopper lock that normally holds a dump door in a closed position, but which is released to permit the door to be swung open upon rotation of the dirt hopper away from the sweeper and which is self locking upon return of the hopper to its original position.

Still another important object of this invention is to provide a new and improved dirt handling mechanism in combination with a self releasing hopper lock to permit improved controlled loading and unloading of the dirt hopper.

A still further object of this invention is to provide an economical self operating releasable hopper lock that can be operated through the extension and retraction of linkage comprising components of the dirt hopper handling mechanism and without any additional hydraulic means, or the like.

Still another important object of this invention is to provide a self releasing and self locking hopper lock which is actuata'ble when the dirt hopper is at a street level position or at an elevated position.

According to this invention, the self releasing hopper lock can be released when the dirt hopper is moved through an are at a street level position to permit sweepings to be loaded into a truck or stacked in large rather than small piles.

Other objects and features of this invention will more fully become apparent in=view of the following detailed description taken in conjunction with the accompanying drawings illustrating therein a single embodiment and in which:

On the drawings:

FIGURE 1 is a side view of a street sweeper illustrating the operation of the self releasing hopper lock when the dirt hopper is emptied at a street level position.

FIGURE 2 is an enlarged fragmentary perspective view of the dirt hopper and the hopper lock for securing the hopper door in closed position; and

FIGURE 3 is an enlarged fragmentary opposite side view of the street sweeper shown in FIGURE 1 illustrating in full and dotted lines the operation of the self releasing hopper lock when the dirt hopper is emptied from an elevated position.

As shown on the drawings:

A street sweeper is illustrated as having a sweeper body 11 supported on front and rear wheels 12 and 13. One or more side brooms 14 and a main broom 15 are provided for depositing sweepings onto a conveyor 16 3,312,992 Patented Apr. 11, 1967 (FIGURE 1) so that the sweepings may be deposited into a dirt hopper 17. The controls for operating the sweeper 19, the brooms 14 and 15, the conveyor 16 and the dirt box 17 are operable from an operators seat 18 (FIG- URE 2).

The dirt hopper 17 has a bottom 19, an upwardly inclined forward wall 20 and an upwardly and rearwardly inclined wall 21 with a hopper door 22 pivotally joined at its upper end by means of hinges 23. A hopper scoop 24 lies in the plane or are of the upwardly and rearwardly inclined or arcuate wall 21. The scoop 24 further defines a sweepings inlet 25 (FIGURE 1). The dirt hopper 17 further includes a rear wall 26 and side walls 27. When the dirt hopper is in sweeping position, the scoop snugly cooperates with upper sweeper body wall 28 to prevent dust from escaping the dirt hopper 17 as it is being loaded by the conveyor 16.

The sweeper body 11 additionally includes side body portions 30 and 31 which are joined with the upper sweeper body wall 28 and extend forwardly thereof to define a dirt hopper housing 32. In order to mount the dirt hopper 17 on the machine, we have developed a new and improved dirt hopper handling mechanism or apparatus embodying important features of this invention, which is claimed in our copending application for patent entitled Street Sweeper Dirt Box Assembly, Ser. No. 359,699 now US. Patent 3,162,877. This apparatus or mechanism includes the following described components. A pair of dirt hopper carrying hollow side beams or arms 33 and 34 are pivotally joined to the side body portions 30 and 31 at pivots 35 and 36, The beams 33 and 34 are joined at opposite ends with the side walls 27 of the dirt hopper 17 at pivots 37 and 38.

A pair of fluid cylinders 39 and 40 having rams 41 and 42 are provided for raising and lowering the beams 33 and 34 and the dirt hopper 17 carried thereon. The cylinders 39 and 40 are each pivotally supported on pivots 43 at one end on the sweeper body 11 and the rams 41 and 42 each project into a hollow area 45 of the associated one of the beams. The rams 41 and 42 are joined with the beams at pivots 44. Each of the rams and its associated beam are disposed in a common vertical plane so that the elevating mechanisms may be as compact as possible. By providing compact elevating mechanisms, the largest possible dirt hopper 17 may be used on the sweeper machine 10.

Linkage and means are also provided for rotating the dirt hopper 17 on the beams 33 and 34 to dump the contents of the hopper past the swinging door 22 through the dirt box outlet. This linkage and dirt hopper rotating means at each side of the dirt hopper are also disposed in vertical planes common with the vertical planes of the beams 33 and 34 for compactness as previously described. To this end, identical linkages and 51 are provided on opposite sides of the dirt hopper 17. Since the linkages 50 and 51 are identical a description of one will suflice for both.

The linkage 51 includes a pair of first spaced parallel links 53 (FIGURE 1) which are joined at one end at pivots 54 to opposite sides of the associated beam 34. A second link 55 is joined at one end at pivot 56 between and with opposite ends of the spaced links 53 and at an opposite end at pivot 57 with the side wall 27 of the dirt hopper 17.

Mounted on the beams 33 and 34 and cooperable with the linkages 50 and 51 are a pair of fluid cylinders 60 and 61 for rotating the dirt hopper 17. The cylinders 60 and 61 are pivotally joined with the beams 33 and 34 at pivots 64 and 65 and the rams 62 and 63 are pivotally joined with the linkages 50 and 51 at pivots 66 and 67 and more particularly with the links 53.

The scoop 24 also serves another important function in that it provides a body housing closure to prevent dust from escaping from the sweeper as the machine is being used to sweep the streets. It will be appreciated that the scoop 24 may be eliminated, if desired, as the scoop is an optional feature.

Some of the advantages of our new sweeper are evident from the drawings wherein the diiferent uses of the machine are illustrated. FIGURE 3 illustrates the manner in which the dirt hopper 17 can be elevated and dumped so that sweepings may be dumped directly into a truck, or railroad car or other type vehicle so that a savings may be effected in the handling of the sweepings. Where a truck is unavailable the sweepings can be dumped into large piles rather than in many small piles. Either type of operation is particularly useful in city areas where dump areas are scarce and expensive. By providing a sweeping machine that can dump in such a way that large piles can be produced, the dump areas can be more efficiently utilized. When the dirt hopper 17 is turned upside down, the door 22 flops open and the contents of the hopper are emptied.

FIGURE 1 illustrates the manner in which the dirt hopper 17 can be emptied where it is not desired to unload the dirt hopper 17 from an elevated position, such as on a windy day.

Our sweeper machine 10 can also be effectively used as a front end loader for dozing or pickup operations if desired. As the dirt hopper 17 is moved in a pickup operation, rocks, sweepingsand other materials are caused to flow through the dirt box opening normally employed as an inlet for sweepings when the machine 10 is being operated as a street sweeper.

According to important features of this invention, a pair of self releasing hopper locks 100 are provided to hold the hopper door shut or closed during a dozing operation and at all times except when the hopper is rotated through an arc when being emptied. The hopper locks 100 are each identical in construction and a description of one will suffice for the other. The hopper locks comprise a pair of extensions or lugs 101 which extend outwardly in a transverse direction from opposite sides of the dump door 22. These extensions or lugs 101 can be suitably secured to the dump door such as by means of 'welds and the like. The locks 100 also include a pair of hooks 102 which are secured to forward ends of the arms 33 and 34. These hooks can be secured in any suitable manner to the arms such as by welds and the like. It will further be noted that each of the hooks 102 is provided with a lug or extension receiving downwardly facing hook groove 103. By way of explanation, the hook grooves face downwardly when the hopper 17 is in position for receiving sweepings or in position for road travel to and from a dump. When the arms 33 and 34 are elevated, the lug receiving grooves 103 are also rotated from a downwardly facing position disposed forwardly of the door pivot or hinge 23 to a rearwardly facing position. Upon actuation of the cylinders 60 and 61, the hinge pivot 23 is moved from a position rearward of the hooks 102 to a position forward of the hooks 102 enabling the lugs 103 to swing free of the hooks 102.

In operation, when the hopper 17 is to be unloaded, from a street level position, the fluid cylinders 60 and 61 are actuated causing the dirt hopper 17 to be rotated forwardly from the pivots disposed at the forward ends of the arms 33 and 34. As the hopper is rotated, the lugs or extensions 101 swing free from the grooves 103 on the hooks 102 in a self releasing manner permitting the contents of the hopper to be discharged therefrom. It will be perceived from the drawings that the door 22 is hinged at 23 which hinge is disposed on an axis that extends transversely of the door and of the sweeper. Then, after the contents of the hopper 17 have been emptied, the hopper is again swung on its pivots 37 and 38 back to its original position for reeciving sweepings. As the hopper is rotated, relative movement occurs between the lugs 101 and the door 22 with respect to the hopper 17 in such a manner that the lugs are re-engaged in the hook grooves 103 on the hooks 102 in a self locking manner. In the operation of the locks 100, relative movement occurs between the hopper 17 and the door 22 in order to effect engagement and disengagement of the lugs relative to the hooks 102. The locks 101 can only be released when the hopper is swung on its pivots 37 and 38. When the hopper 17 is to be emptied from an elevated position, it is raised in'the same manner as previously described and the locks are operated as the hopper is rotated in the same manner as already described above.

By providing a front end loader on the sweeper, the sweeper can be used for longer daily periods as a street sweeper since the travel time of a loaded sweeper from the sweeping area to a dump area can be greatly reduced. The loaded sweeper can dump directly into a truck or dump locally in the streets until trucks arrive to carry off the accumulated sweepings. When hauling vehicles become available the front end loader on the sweeper can be used to pick up the piles of sweepings and load them thereon. In the past, especially around large cities, it has been necessary for the sweeper operators to drive long distances to dump loaded dirt hoppers, thus reducing the amount of time per day that the sweeper could be used in sweeping the streets.

When the hopper has a maximum load and it is elevated, the center of gravity of the load is maintained in close proximity to the sweeper so that the load will be stabilized at all times and so that it is not necessary to provide accessory counterbalancing means on the opposite end of the sweeper. When the hopper is unloaded and rotated away from the'sweeper the balance of the sweeper is not upset as the hopper is unloaded while the hopper is being rotated.

Although minor modifications might be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon, all such modifications as reasonably and properly come within the scope of our contribution to the art.

We claim as our invention:

1. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper provided with a sweepings inlet mounted in said body opening and having a dump door thereon,

the door being pivotally secured at its upper end to said hopper and being suspended from this pivot as a closure for a hopper discharge opening,

means for directing sweepings into said sweepings inlet,

means joining said dirt hopper with said body for elevating said dirt hopper,

means for turning over said dirt hopper through an arc in a direction away from the body to unload the dirt hopper, and

self releasing hopper lock means coopera-ble with opposite sides of the dirt hopper for securing a lower end of the dump door on the dirt hopper in a closed position until said dirt hopper is moved through an arc in a direction away from the body by operation of said means for turning over said dirt hopper through an are.

2. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper provided with a sweepings inlet mounted in said 'body opening,

the door being pivotally secured at its upper end to said hopper and being suspended from this pivot as hopper when said dirt hopper is in a street levelposition or in an elevated position,

a dump door on said dirt hopper, and

self releasing hopper lock means cooperable with opposite sides of the dirt hopper for securing a lower end of the dump door on the dirt hopper in a closed position and releasable when said dirt hopper is moved through an arc in a direction away from the body by operation of said means for turning over said dirt hopper through an arc.

3. In combination in a street sweeping machine,

a body provided with an upwardly and forwardly opening dirt hop-per housing,

a dirt hopper disposed in said housing and having a swingably mounted hopper door extended along an upper surface of the dirt hopper and having a sweepings inlet positioned rearwardly of the swingable door for receiving sweepings,

means comprising a pair of side arms for suspending the dirt hopper from the machine with said arms being mounted on :arm pivots at rearward ends on said body and pivotally attached at opposite ends with opposite sides of said dirt hopper,

means for pivoting said arms on said arm pivots for raising and lowering said dirt hopper comprising a first pair of fluid cylinders attached to said body and having rams attached to said side arms on opposite sides of said hopper and disposed in coplanar relation with said arms therewith for compactness,

self releasing hopper lock means cooperable with opposite sides of the dirt hopper for securing the hopper door on the dirt hopper in a closed position until said dirt hopper is moved through an arc in a direction away from the body, and

means coplanar with said arms for rotating said dirt hopper on its pivots where joined with said side :arms comprising linkage on opposite sides of said dirt hopper joining said arms with said hopper and a second pair of fluid cylinders including a second pair of rams with said second pair of fluid cylinders joined at ends with said arms and with said second pair of rams joined at opposite ends with said linkages whereby the dirt hopper may be elevated and moved through an arc to turn the dirt hopper to allow the hopper door to swing open for the sweepings to fall through a discharge outlet.

4. Incombination in a street sweeping machine,

a body provided with an upwardly and forwardly open dirt hopper housing,

a dirt hopper disposed in said housing and having a swingably mounted hopper door extended along an upper surface of the dirt hopper and having a sweepings inlet positioned rearwardly of the swingable door for receiving sweepings,

means comprising a pair of side arms for suspending the dirt hopper from the machine with said arms being mounted on arm pivots at rearward ends on said body and pivotally attached at opposite ends with opposite sides of said dirt hopper,

means for pivoting said arms on said arm pivots for raising and lowering said dirt hopper comprising a first pair of fluid cylinders attached to said body and having rams attached to said side arms on opposite sides of said hopper and disposed in coplanar relation with said arms therewith for compactness,

self releasing hopper lock means cooperable with opposite sides of the dirt hopper for securing the hopper door on the dirt hopper in a closed position and releasable when said dirt hopper is moved through an arc in a direction away from the body,

said self releasing hopper lock means comprising a pair of hooks mounted on said side arms and a pair of extensions extending transversely and outwardly from opposite sides of said hopper door and releasably engaged with said hooks, and

means coplanar with said arms for rotating said dirt hopper on its pivots where joined with said side arms comprising linkage on opposite sides of said dirt hopper joining said arms With said hopper land a second pair of fluid cylinders including a second pair of rams with said second pair of fluid cylinders joined at ends with said arms and with said second pair of rams joined at opposite ends with said linkages whereby the dirt hopper may be elevated and moved through an arc to turn the dirt hopper to allow the hopper door to swing open for the sweepings to fall through a discharge outlet. 5. In a street sweeping machine, a body provided with an upwardly and forwardly opening dirt hopper housing, means for sweeping a surface over which the machine is directed and delivering the sweepings to said dirt hopper housing,

a dirt hopper disposed in said housing and having a swingably mounted hopper door extended along an upper surface of the dirt hopper and having a sweepings inlet positioned rearwardly of the swingable door for receiving sweepings from said means,

means comprising a pair of side arms for suspending the dirt hopper from the body with said arms being mounted on arm pivots at rearward ends on said body and pivotally attached at opposite ends with opposite sides of said dirt hopper,

means for pivoting said arms on said arm pivots for raising and lowering said dirt hopper comprising a first pair of fluid cylinders pivotally attached to said body and to said side arms and joined in coplanar relation therewith for compactness,

self releasing hopper lock means cooperable with the dirt hopper for securing the hopper door on the dirt hopper in a closed position until said dirt hopper is moved through an arc in a direction away from the body, and

means coplanar with said arms for rotating said dirt hopper on its pivots where joined with said side arms comprising linkage on opposite sides of said dirt hopper joining said arms with said hopper and a second pair of fluid cylinders joined at ends with said arms and joined at opposite ends with said linkages whereby the dirt hopper may be elevated and moved through an arc to turn the dirt hopper to allow the hopper door to swing open for the sweepings to fall through a discharge outlet.

6. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper provided with a sweepings inlet mounted in said body opening and a dump door suspended on an axis from a lower front end of the dirt hopper,

means for directing sweepings into said sweepings inlet,

means comprising arms joining said dirt hopper with said body for elevating said dirt hopper,

means for moving said dirt hopper through an arc in a direction away from the body to unload the dirt hopper when said dirt hopper is in a street level position or in an elevated position, and

self releasing hopper lock; means cooperable with the dump door and the dirt hopper for securing the dump door on the dirt hopper in a closed position and for releasing the dump door when said dirt hopper is moved through an arc in a direction away from the arms enabling the dump door and the dirt hopper to move relative to one another for emptying the contents of said dirt hopper.

7. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper provided with a sweepings inlet mounted in said body opening and a dump door suspended on an axis from a lower front end of the dirt hopper,

means for directing sweepings into said sweepings inlet,

means comprising arms joining said dirt hopper with said body for elevating said dirt hopper,

means for moving said dirt hopper through an arc in a direction away from the body to unload the dirt hopper when said dirt hopper is in a street level position or in an elevated position, and

means cooperable with the dirt hopper for securing the dump door on the dirt hopper in a closed position and for releasing the dump door when said dirt hopper is moved through an arc in a direction away from the arms enabling the dump door and the dirt hopper to move relative to one another for emptying the contents of said dirt hopper, said last mentioned means comprising a pair of hooks mounted on said means joining said dirt hopper with said body and a pair of extensions carried on and extending outwardly in a transverse direction from opposite sides of said dump door.

8. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper having a hopper door at a lower end of its front end and which door has a transverse pivot axis at its upper end permitting forward and rearward movement of the door relative to the hopper and with the hopper provided with a sweepings inlet mounted in said body opening rearwardly of said hopper door,

means for directing sweepings into said sweepings inlet,

pivot means joining said dirt hopper with said body,

means for elevating said dirt hopper,

hopper turning means for moving said dirt hopper on said pivot means through an arc in a direction away from the body, and

self releasing and locking hopper lock means cooperable with said hopper turning means and with the dirt hopper for securing the hopper door on the dirt hopper in a closed position until said dirt hopper is moved forwardly through an arc in a direction away from the body and for locking the hopper door to the dirt hopper upon moving the dirt hopper rearwardly through an arc toward the body.

9. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper mounted on pivots in said body opening and having a hopper door swingable from a door pivot at its upper end and provided with a sweepings inlet mounted in said body opening rearwardly of said door,

means for directing sweepings into said sweepings inlet,

means for elevating said dirt hopper,

self releasing hopper lock means cooperable with the dirt hopper and positioned forwardly of said door pivot for securing the hopper door on the dirt hopper in a closed position and releasable when said dirt hopper is moved through an arc in a direction away from the body and when said door pivotis moved to a position forward ofsaid hopper lock means, and

means for moving said dirt hopper through an arc in a longitudinal direction away from the body and cooperable with said self releasing hopper lock means to unload the dirt hopper when said dirt hopper is in a street level position or in an elevated position.

10. A street sweeper comprising,

'a body having a body opening for a dirt hopper, a pair of arms pivotally mounted in said body opening,

a dirt hopper mounted on pivots on said arms and having a hopper door swingable from a door pivot at its upper end and provided with a sweepings inlet mounted in said body opening rearwardly of said door,

means for directing sweepings into said sweepings inlet,

means for elevating said arms and said dirthopper,

self releasing and locking hopper lock means cooperable with a lower end of the dirt hopper and positioned forwardly of said door pivot for securing the hopper door on the dirt hopper in a closed position and releasable when said dirt hopper is moved through an arc in a direction away from the body and when said door pivot is moved to a position forward of said hopper upwardly lock means and self locking when said door pivot is moved in an arc toward the body rearwardly of said hopper lock means, and

means for moving said dirt hopper through an arc generally in a longitudinal direction away from the body and said arms and cooperable with said hopper lock means for unloading the dirt hopper.

11. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a dirt hopper having a hopper door at a lower end of its front end and which door has a transverse pivot axis at its upper end permitting forward and rearward movement of the door relative to the hopper and with the hopper provided with a sweepings inlet mounted in said body opening rearwardly of said hopper door,

means for directing sweepings into said sweepings inlet, pivot means joining said dirt hopper with said body,

means forelevating said dirt hopper,

hopper turning means for moving said dirt hopper on said pivot means through an arc in a direction away from the body at a street level position and at an elevated position, and

self releasing and locking hopper lock means comprising a pair of lugs mounted on opposite sides of said door and a pair of hooks mounted at opposite sides of said body for locking engagement with said lugs and with the hooks and lugs being disposed longitudinally on one side of said transverse pivot axis when said door is in a closed position and with said hooks being disposed on an opposite side when said door is in an unlocked position.

said lugs and said hooks being cooperable with said hopper turning means and with the dirt hopper for securing the hopper door on the dirt hopper in a closed position until said dirt hopper is moved forwardly through an arc in a direction away from the body and for locking the hopper door to the dirt hopper upon moving the dirt hopper rearwardly through an arc toward the body.

12. A street sweeper comprising,

a body having a body opening for a dirt hopper,

a pair of arms pivotally mounted in said body opening,

7 a dirt hopper mounted on pivots on said arms and having a hopper door swingable from a door pivot at its upper end, 7

means for elevating said arms and said dirt hopper,

self releasing and locking hopper lock means cooperable with the dirt hopper and positioned forwardly of said door pivot for securing the hopper door on the dirt hopper in a closed position and releasable when said dirt hopper is moved through an arc in a direction away from the body as said door pivot is moved to a position forward of a lower end of said door and self locking as said door pivot is moved in an are past the lower end of the door in an opposite direction, and means for moving said dirt hopper through an arcin a longitudinal direction away from the body and said arms and cooperable with'said self releasing hopper lock means to unload the dirt hopper when said dirt hopper .is in a street level position or in an elevated position.

13. A street sweeper comprising,

a body having a body opening for a dirt hopper,

arms joined at one end with said body,

a dirt hopper pivotally carried on said arms and having a hopper door at a lower end of its front end and which door has a transverse pivot axis at its upper end permitting forward and rearward movement of the door relative to the hopper,

hopper turning means for pivotally moving said dirt hopper relative to said arms through an arc in a direction away from the body at a street level position and at an elevated position, and

self releasing and locking hopper lock means comprising a pair of lugs mounted on opposite sides of said door and a pair of hooks mounted at opposite sides of said body on said arms for locking engagement with said lugs and with said transverse pivot axis being disposed on one side of said hooks when said door is in a closed position and on an opposite side of said hooks when said door is in an unlocked position,

said lugs and said hooks being cooperable with said hopper turning means and with the dirt hopper for securing the hopper door on the dirt hopper in a closed position until said dirt hopper is moved forwardly through an arc in a direction away from the body and for locking the hopper door to the dirt hopper upon moving the dirt hopper rearwardly through an arc toward the body.

14. A street sweeper comprising,

a body,

a dirt hopper provided with a sweepings inlet and a discharge outlet adjacent thereto,

means for directing sweepings into said sweepings inlet,

arm means joining said dirt hopper with said body,

means for elevating said dirt hopper,

a dump door swingably mounted on said dirt hopper,

self releasable latch means joining said door with said hopper, and

means for turning said dirt hopper over and outwardly beyond said arm means to place the dirt hopper in an unloading position and thereby operating the releasable latch means allowing movement of the dump door to discharge the contents of said hopper.

15. A street sweeper comprising,

a body,

a dirt hopper provided with a sweepings inlet,

support means joining said dirt hopper with said body,

means for directing sweepings into said sweepings inlet,

a dump door positioned generally on a 'front side of the dirt hopper and swingable on a horizontal axis,

means for elevating said dirt hopper,

self-releasing latch means joining the dump door to the body and positioned outwardly of the horizontal axis of the door when the door is closed, and

means for rolling over said dirt hopper relative to said support means in a direction away from said body moving the horizontal axis of the door outwardly beyond the self-releasing latch means releasing the same and placing the dirt hopper and its door in a position for dumping.

References Cited by the Examiner UNITED STATES PATENTS 1,459,385 6/1923 Wills et al.

1,800,824 4/1931 Evans 21489 2,829,391 4/1958 Swanson 15-83 3,162,877 12/1964 Schmidt et a1. 1583 CHARLES A. WILLMUTH, Primary Examiner. S. E. BECK, Assistant Examiner. 

14. A STREET SWEEPER COMPRISING, A BODY, A DIRT HOPPER PROVIDED WITH A SWEEPINGS INLET AND A DISCHARGE OUTLET ADJACENT THERETO, MEANS FOR DIRECTING SWEEPINGS INTO SAID SWEEPINGS INLET, ARM MEANS JOINING SAID DIRT HOPPER WITH SAID BODY, MEANS FOR ELEVATING SAID DIRT HOPPER, A DUMP DOOR SWINGABLY MOUNTED ON SAID DIRT HOPPER, SELF RELEASABLE LATCH MEANS JOINING SAID DOOR WITH SAID HOPPER, AND MEANS FOR TURNING SAID DIRT HOPPER OVER AND OUTWARDLY BEYOND SAID ARM MEANS TO PLACE THE DIRT HOPPER IN AN UNLOADING POSITION AND THEREBY OPERATING THE RELEASABLE LATCH MEANS ALLOWING MOVEMENT OF THE DUMP DOOR TO DISCHARGE THE CONTENTS OF SAID HOPPER. 